Title

A Simple Solution to Heating

Problem Scenario

People say that if you wear a dark colored shirt on a hot day that you are going to become warmer that somebody that is wear a lighter color, but how much warmer will you really become?

Broad Question

Is there a correlation between the color of an object and its temperature?

Specific Question

How does the color of a piece of cloth affect the temperature that it gains when light is shone on it?

Hypothesis

It is hypothesized that the black cloth will become warmer than the other colors of cloth (grey and white) after all of the pieces of cloth are exposed to the same amount of light.

Graph of Hypothesis

Variables

Independent Variable:

Color of Cloth (Black, Gray, White)

Dependent Variable:

Temperature of Cloth...
-Temperature of the cloth
-Surface temperature of the cloth

Variables That Need To Be Controlled:

-Type of flood light
-Amount of time in light
-Type of fabric
-Size of fabric
-Material below fabric
-Distance infrared thermometer is away from the cloth
-Where cloth is, in relation to the light

Vocabulary List That Needs Explanation

Albedo - the ratio of the amount of light reflected to the amount of light absorbed
Angstrom - a unit of measurement equivalent to one nano-meter

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General Plan

An experiment was conducted within Mr. Yahna’s classroom. The goal of this experiment was to see how the color an object affects the temperature of it, when light hits it. The color of the cloth was intentionally changed to see if it would affect the temperature. To do this, 3 pieces of cloth were purchased from Walmart. A flood light, infrared thermometer, and passport thermometers were used. A computer, which displayed the data of the thermometers was also used to make sure that all of the pieces of cloth had the light shown on them for the same amount of time. While the light was shown on the cloth, the temperatures were recorded. Finally, the mean and median temperatures were determined for each color of the cloth.

Potential Problems And Solutions

Problem: Some pieces of cloth will have more light shone on them than others.
Solution: Each piece of cloth will rotate into all of the positions and their temperatures will be averaged.

Safety Or Environmental Concerns

There are no safety or environmental concerns for this experiment.

Experimental Design

Controlled, manipulated experiment

Number Of Trials:

There will 3 different trials in this experiment. (black, grey and white pieces of cloth)

Number Of Subjects In Each trial:

Each color of cloth (subjects) will have one subject in each trial.

When data will be collected

The data will be collected after each piece of cloth has been exposed to the same amount of light for 5 minutes.

Number of Observations:

Each piece of cloth will be observed twice. They will be observed before the light is shone on the and after 5 minutes of light.

Where will data be collected?:

The data will be conducted on a table in Mr. Yahna's classroom.

Resources and Budget Table

Data Tables

Time Line

March 3rd - complete design and collection of all materials (jbes)
March 5th - run a test of the set up, not collecting data, just seeing if everything works (jbes)
March 6th - run first official trials of experiment, collect first data (jbes)
March 30th - complete all trials of experiment and all data collection (jbes)
April 1st - complete all data analysis ; mean, median, range, graphs (home)
April 8th - complete results and conclusions write up (home)

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Background Research

- Temperature/heat is the vibrations of molecules and atoms.
- In a thermometer, the mercury expands when it gets warmers
- In electronic thermometers, inside the probe on the end, a micro controller measures the resistance of electricity flowing metal. When metal gets hotter for ex the atoms in it jiggle faster, causing more Resistance to the electricity that is trying to flow through it. This resistance is measured and is converted to temperature
- Heat is a form of energy

- color is created by different wave lengths
- visible light waves are about the size of bacteria
- wave lengths are measured in angstroms which are about a ten-billionth of the the meter
- red has larger wave lengths (7,000 angstroms)
- violet has smaller wave lengths (4,000 angstroms)
- Order of Wave Length Size (Red>Orange>Yellow>Green>Blue>Violet)

Colors such as black absorb more wave lengths than white. For example, black can absorb infrared, while white will reflect it. Simply, black reflects the least amount of wavelengths.

If an objects absorbs all wavelengths, it appears black
If it reflects all wavelengths, it appears white.
Albedo is the ratio between the amount of light an object reflects to the amount of radiation hitting it. It is often referred to as a percentage 100% being pure white (reflecting all rays) The higher the percent is, the color the object will be with the same amount of light.

References

__http://skyserver.sdss.org/dr1/en/proj/advanced/color/whatis.asp__
__http://answers.ask.com/Reference/Other/how_big_is_an_angstrom__
__http://en.wikipedia.org/wiki/Angstrom__
__http://en.wikipedia.org/wiki/Temperature__
__http://www.ehow.com/how-does_5162287_electronic-thermometer-work.html__
__http://en.wikipedia.org/wiki/Sun__
__http://answers.yahoo.com/question/index?qid=20090202142410AAu6jUO__
__http://www.explainthatstuff.com/thermometers.html__
__http://en.wikipedia.org/wiki/Color__
__http://en.wikipedia.org/wiki/Albedo__

Detailed Procedure

1. Gather all of the materials (1 piece of black cloth, 1 piece of gray cloth, 1 piece of white cloth, a computer, 3 passport thermometers, passport thermometer splitter, infrared thermometer, flood light, flood light mount, table, ruler, scissors, paper, a pencil, saw, and insulation).
2. Cut each pieces of cloth into 20 cm x 20 cm squares (one of each color).
3. Cut the insulation into three 20 cm x 20 cm squares
4. Use the flood light mount to suspend the flood light 45 cm in the air, facing directly downwards onto the table.
5. Use the ruler find exact length of the arm on the flood light.
6. Measure and mark this distance from the base of the mount, staying directly below the arm.
7. Place the cloth so that each piece has two of its corners touching two corners of a different piece. The space in between the squares should create an equilateral triangle. Make sure that the brightest dot of light from the flood light is in the center of the equilateral triangle.
8. Set a piece insulation below the each piece of cloth
9. Start the computer.
10. Hook up the passport thermometers to the passport thermometer splitter.
11. Plug the passport thermometer into the computer
12. Place one passport thermometer below each square piece of cloth, but above each piece of insulation. The wire of the thermometer should come out on the side opposite of the light and the tip of the thermometer should go in the center of the cloth.
13. Start having the computer record temperatures (make sure the passport thermometers are recording once every 5 seconds)
14. Turn on the flood light for 5 minutes.
15. Turn off the flood light.
16. Stop having the computer record temperatures.
17. Immediately record the surface temperature of the cloth with the infrared thermometer. Hold the thermometer 7 cm away from the cloth when measuring. This can be made exact by measuring the distance between the cloth and the infrared thermometer with the ruler. Remove the ruler before recording the temperature, but do not move height of the thermometer.
18. Wait for the temperature of the table, cloth, insulation, and flood light to return to room temperature.
19. Move each piece of cloth clockwise to the next position. Each piece of cloth should be on the piece of insulation clockwise.
20. Repeat steps 13 - 18.
21. Move each piece of cloth clockwise to the next position. Each piece of cloth should be on the piece of insulation clockwise.
22. Repeat steps 13 - 18.
23. Check data and make sure experiment is complete.
24. Clean up all materials

Photo List

-Complete set up (aerial)
-Complete set up (45 degree angle)
-All colored pieces of cloth in position
-Using infrared thermometer
-Cutting Cloth
-Cloth with passport thermometer below it
-Light close up
-Recording Temperatures
-Timer
-Computer with current thermometer data

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Results

Out of the three trials that were conducted the black cloth gained the most amount of heat. It had an average gain of 16.3 degrees celsius. The second warmest color of cloth was grey and gained an average of 14.1 degrees celsius. The piece of cloth that gained the least amount of heat was white with 10.7 degrees. The order from warmest to coldest was consistently: black, grey, then white throughout every trial.

All Raw Data

Graphs

Photos

Cutting the Cloth to the Right Shape


Flood Light Shining


Aerial View of Experiment

Thermometer Under Cloth


Cloth Close-up


Measuring the Surface Temperature


Recording Data by Hand


Graph of Live Temperatures

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Data Analysis

Conclusion

An experiment was conducted to test how the color of an object affects its temperature when light was shone on it. The independent variable was the color of the object that the light was shown on. The dependent variable was the temperature that each object gained after five minutes of light. The mean and median were calculated to compare results.The piece of cloth that was black had a higher gained temperature than the other pieces of cloth. It had an average temperature gain of 16.3 degrees Celsius. This was followed by grey, which had a 14.1 degrees C average temperature gain. Finally the white gained only an average of 10.7 degrees Celsius.

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Discussion

An experiment was conducted to test how the color of an object affects the temperature of it when light is shone on it. During the experiment enough results were found to make a conclusion about the experiment. It was discovered that the black cloth became the warmest, followed by grey, then white. It was hypothesized that the black piece of cloth would become warmer than the grey cloth. The white piece of cloth was hypothesized to gain the least amount of heat. This hypothesis was supported by the results of the experiment. The black piece of cloth gained an average of 16.3 degrees C. The grey gained an average of 14.1 degrees C and the white only gained 10.7 degrees celsius. This can be explained because black cloth has an albedo of about 0.07, which means that it is reflecting 7% of the heat. That means that it is absorbing about 93% of the radiation/heat. The grey absorbed only 70% of the heat (albedo of 0.3) . Finally, the white absorbed about 13% (albedo of 0.87). Because the grey and white absorb less heat, it makes sense that they will be cooler than black. This shows that the higher the albedo, the cooler something will be. When the surface temperature was measured after 5 minutes the black piece of cloth was about 57.3 degrees. The grey was 41.5 degrees and the white was 36.8 degrees. When the surface temperature was measured it appeared to have gained more heat than when the actual temperature was measured. It is predicted that this is because the light was shining straight onto the top of the cloth, which would have made the top warmer while the heat would have had to travel all throughout the cloth to get to the regular thermometers.
During the designing of this experiment some problems did occur. The hardest problem was to make sure that all of the pieces of cloth got the same amount of light shone on them. This was controlled by rotating the pieces of cloth into each of the position. One problem during the experiment that arose was that it was difficult to get an exact measuring of the surface temperature. Because only one infrared thermometer was available, only one piece of cloth could be measured at a time, causing the temperature to vary during the time it took to record the temperature. Apart from that, the experiment generally went as planned. This experiment could have been improved by having multiple infrared thermometers so that the temperatures could have been measured at the same time. This would have allowed for more exact results. The surface temperature also should have been measured to start out with, so that the gained temperature could be calculated.
Many pieces of technology were used in this experiment to get accurate results. Many things such as thermometers that could be monitored by the computer were key to this experiment. Knowledge of the albedo effect also assisted in conducting this experiment.

Benefit to Community and/or Science

People can learn from this experiment that the color of an object really does have a huge affect on its temperature. This experiment could help improve many things. This such as houses, planes, cars, and clothing could be improved. If somebody lives where it is hot outside, they could paint their house a light color, to reduce the temperature inside. They could also wear lighter colored clothing to help reflect the sun away. In the same way, a dark colored house or shirt will help attracted heat in the winter. People that design clothing or homes might be interested in knowing this information. This experiment could be used to help many things.

Abstract

An experiment was conducted to test how the color of an object affects its temperature when light was shone on it. The independent variable was the color of the object that the light was shown on. The dependant variable was the temperature that each object gained after five minutes of light. To conduct this experiment a light was shone directly over three pieces of cloth, and the temperatures were monitored on the computer. Three different trials were completed to get more accurate data. The mean and median were calculated to compare results. It was expected that the temperatures would only get to about 33 degrees Celsius, but in reality some of the pieces of cloth reached almost 60 degrees.The piece of cloth that was black had a higher gained temperature than the other pieces of cloth. It had an average temperature gain of 16.3 degrees celsius. This was followed by grey, which had a 14.1 degrees C average temperature gain. Finally the white gained only an average of 10.7 degrees Celsius. The surface temperature was also measured, which showed similar but more exaggerated results. These results could be used to help many things in the real world. For example, darker clothing could be made to help keep the wearer warm.